What is the test to determine whether a defendant has a right to a speedy trial?

"We review the district court's findings of fact as they pertain to a speedy trial challenge for clear error and its legal conclusions de novo." United States v. Lynch, 726 F.3d 346, 351 (2d Cir. 2013). To determine whether a defendant's right to a speedy trial has been violated, "[w]e consider four factors: the '[l]ength of delay, the reason for the delay, the defendant's assertion of his right, and prejudice to the defendant.'" United States v. Black, 918 F.3d 243, 254 (2d Cir. 2019) (citing Barker v. Wingo, 407 U.S. 514, 530 (1972)). No one factor is dispositive. Id.